A lack of sufficient snow on parts of the trail in central Alaska has also contributed to organizers considering a route change.

They would move the official start to Fairbanks, some 300 miles (480 km) north of the traditional location in Willow, a small community about 80 miles (130 km) north of Anchorage, in southern Alaska.

"Certain sections have been iffy the past few years so right now we are putting some attention into sorting through what Plan B would look like right now," race director Stan Hooley said in an interview Thursday evening. "We are working as if we have two parallel plans."

The punishing round-the-clock race commemorates a rescue mission that carried diphtheria serum by sled-dog relay to the coastal community of Nome in 1925.

Last year, 26-year-old Dallas Seavey and his canine team finished the roughly 1,000-mile (1,600-km) race through the Alaskan tundra and into Nome in 8 days, 13 hours, 4 minutes and 19 seconds.

So far 80 mushers, including two-time winner and defending champion Seavey, have registered to compete, some coming from as far away as Norway, New Zealand, Sweden and France.

Last month, race organizers announced an additional $50,000 in prize money for the top five finishers. The winner will claim $70,000, almost $20,000 more than last year.

The ceremonial start in Anchorage is slated for March 7, and officials will have the route selected by Feb. 15, Hooley said.

Race organizers last moved the race to Fairbanks in 2003.

They also considered a move last year and faced criticism from mushers for not changing the route after several racers had trouble navigating one of the steeper and more challenging sections of the trail. Mushers also said the trail's snowless sections were too dangerous.

Hooley said the organizers spent a lot of time during the summer clearing potential hazards such as exposed tree roots in the areas criticized as unsafe.

He said officials are concerned about a 100-mile (160-km)stretch between the checkpoints of Rainy Pass and Nikolai along the Alaska Range.

"But we can't let ourselves get too overly anxious to what the circumstances are today because that could change this afternoon," Hooley said.